Search found 45 matches

by halkun
Sun Feb 08, 2026 3:03 am
Forum: Programming
Topic: Reverse Engineered Source Code for Raiders Of The Lost Ark
Replies: 5
Views: 579

Re: Reverse Engineered Source Code for Raiders Of The Lost A

I MASSIVELY updated the readme on the repo and also cleaned up some variable names
by halkun
Sat Feb 07, 2026 7:43 am
Forum: Programming
Topic: Reverse Engineered Source Code for Raiders Of The Lost Ark
Replies: 5
Views: 579

Reverse Engineered Source Code for Raiders Of The Lost Ark

Hi All,
I stayed up way too lat finishing this, but I just wanted to share a project I was working on.
It started as me trying to figure out how to get the maximum "diamonds" to be able to "touch the ark" at the end of the game (Note: You can't)
but along with some other helpful partially complete ...
by halkun
Sat Jan 03, 2026 10:06 am
Forum: Programming
Topic: NEW NES BASIC
Replies: 1
Views: 879

NEW NES BASIC

Hi All!
So I've been working with porting BASIC to the NES and I recently released an alpha version in the wild. Even runs on real hardware!
Sadly, I tried to attach the ROM here, but it didn't like it. I can change the extension.. I mean.. I own the rights to the ROM :)

Here is a rundown of what ...
by halkun
Sat Oct 22, 2022 8:08 am
Forum: Programming
Topic: GeckOS not compiling? No Preprosser in XA?
Replies: 6
Views: 4256

Re: GeckOS not compiling? No Preprosser in XA?

The links don't look correct
$ ls -lah lib6502.i65
lrwxrwxrwx 1 halku halku 21 Oct 22 02:21 lib6502.i65 -> ../lib6502/libjmp.a65

That is how it is in the repo as well. There is no /lib6502/lib6502.i65 -- just a /lib6502/lib6502.a65 that is it's own file.

==EDIT==
I decided to just set up Linux as ...
by halkun
Fri Oct 21, 2022 12:22 am
Forum: Programming
Topic: GeckOS not compiling? No Preprosser in XA?
Replies: 6
Views: 4256

Re: GeckOS not compiling? No Preprosser in XA?

Gockos 2.1 Right from Git.

I compiled xa v2.3.13.

This is all under Cygwin (I don't have an extra machine to put Linux on so I grabbed the next best thing.)

xa compiled and created xa reloc65 ldo65 file65 printcbm uncpk (Well, technically, they all end in .exe)

when I run make in GeckOS, this ...
by halkun
Mon Oct 17, 2022 12:57 am
Forum: Programming
Topic: GeckOS not compiling? No Preprosser in XA?
Replies: 6
Views: 4256

GeckOS not compiling? No Preprosser in XA?

So I'm trying to compile GeckOS from scratch and for some reason XA (Which I also just compiled (v2.3.13)) doesn't recognize any of the preprosseor stuff in the code and spits back syntax errors. The documentation says it should be using a preprosseor but none of the Makefiles seem to reference it ...
by halkun
Sat Feb 09, 2019 2:36 am
Forum: EhBASIC
Topic: EhBasic for the NES... Copyright status?
Replies: 14
Views: 22480

EhBasic for the NES... Copyright status?

So I'm porting EhBasic to the NES and was contemplating getting a commercial license. Sadly, since Lee has died, I was wondering how would you handle the copyright status as this is now officially an orphaned work?

If anything here's at least a screenshot of progress...
http://forum.6502.org ...
by halkun
Thu Feb 07, 2019 8:31 am
Forum: Programming
Topic: Branching is kicking my rear end
Replies: 9
Views: 1179

Branching is kicking my rear end

I want to test if a value located at $EA is 0 or 1. if it's a 1, I want to repeat the test until it turns into a 0. I know I can use AND or BIT but my branching skills are weak. How do I test this?

Loop:
lda $#01
and $EA
BPL loop

something like that?

Also, How would I effectively use BIT to do ...
by halkun
Mon Dec 19, 2016 5:01 pm
Forum: Hardware
Topic: 6502 Block Diagram
Replies: 15
Views: 2634

Re: 6502 Block Diagram

I contemplating of maybe doing a taking further taking the blocks and further breaking them down... Things like the registers should be pretty straight forward with a bunch if parallel D-Latches with a few enable lines.

I was looking at the decode rom on the 6507 schematics , but the markings they ...
by halkun
Sun Dec 18, 2016 7:12 pm
Forum: Hardware
Topic: 6502 Block Diagram
Replies: 15
Views: 2634

Re: 6502 Block Diagram

Augh! I can change the font on the SVG to one that puts a marker on the Zero. As of right now the signal lines names are consistent. I'm assuming that the negated lines in your diagram snippet are internal to the decode block.

I would love to re-do the original plans in SVG too, if anything to get ...
by halkun
Sun Dec 18, 2016 8:15 am
Forum: Hardware
Topic: 6502 Block Diagram
Replies: 15
Views: 2634

Re: 6502 Block Diagram

Well done! SVG is good - perhaps as a first step, zip it and attach it here.

Donald Hanson did his own cleanup - he's the author of the original - and you can see it here:
http://www.witwright.com/DonPub/6502-Block-Diagram.pdf

If you got yours and his at the same scale, you could flip between ...
by halkun
Sun Dec 18, 2016 5:50 am
Forum: Hardware
Topic: 6502 Block Diagram
Replies: 15
Views: 2634

Re: 6502 Block Diagram

Thanks for the spell check... That one got by me. I was trying so hard just making sure all the signal names were correct, didn't catch the big things

I updated the picture BTW.
by halkun
Sat Dec 17, 2016 11:44 pm
Forum: Hardware
Topic: 6502 Block Diagram
Replies: 15
Views: 2634

6502 Block Diagram

So to better learn the 6502 and to give a little to the community, I decided to update the 6502 block diagram. It was looking ragged as a low-resolution scan of a document from the 1970s anyway. I've updated it to SVG, put it on A4 dimensions and did an export at 300 DPI for you all.

I did a Little ...
by halkun
Wed Dec 07, 2016 8:35 pm
Forum: Emulation and Simulation
Topic: Gate-level schematics of 6502?
Replies: 8
Views: 20117

Re: Gate-level schematics of 6502?

Wow! You guys are quick! I'll digest this later when I get home. I just came across the Logisim bi-directional bus problem. I may get away with doing things on the block level and some creative bus management.

In course I'm writing, I was thinking of gluing together a bunch generic 74xx chips ...
by halkun
Wed Dec 07, 2016 5:53 pm
Forum: Emulation and Simulation
Topic: Gate-level schematics of 6502?
Replies: 8
Views: 20117

Gate-level schematics of 6502?

Does there exist a gate-level schematic diagram of the 6502? I was thinking about simulating it in a logic gate simulator, and the most I have found is a block diagram (that I've read may be inaccurate)

I would like to use the 6502 for a class on beginner chip architecture. (Kind of like how C ...